Modern computing and display technologies have facilitated the development of systems for so called “virtual reality” or “augmented reality” experiences, wherein digitally reproduced images or portions thereof are presented to a user in a manner wherein they seem to be, or may be perceived as, real. A virtual reality, or “VR”, scenario typically involves presentation of digital or virtual image information without transparency to actual real-world visual input. An augmented reality, or “AR”, scenario typically involves presentation of digital or virtual image information as an augmentation to visualization of the actual world around the user. For example, referring to FIG. 1, an augmented reality scene (4) is depicted wherein a user of an AR technology sees a real-world park-like setting (6) featuring people, trees, buildings in the background, and a concrete platform (1120). In addition to these items, the user of the AR technology also perceives that he “sees” a robot statue (1110) standing upon the real-world platform (1120), and a cartoon-like avatar character (2) flying by which seems to be a personification of a bumble bee, even though these elements (2, 1110) do not exist in the real world. As it turns out, the human visual perception system is very complex, and producing a VR or AR technology that facilitates a comfortable, natural-feeling, rich presentation of virtual image elements amongst other virtual or real-world imagery elements is challenging.
There are numerous challenges when it comes to presenting 3D virtual content to a user of an AR system. A central premise of presenting 3D content to a user involves creating a perception of multiple depths. In other words, it may be desirable that some virtual content appear closer to the user, while other virtual content appear to be coming from farther away. Thus, to achieve 3D perception, the AR system should be configured to deliver virtual content at different focal planes relative to the user.
In order for a 3D display to produce a true sensation of depth, and more specifically, a simulated sensation of surface depth, it is desirable for each point in the display's visual field to generate the accommodative response corresponding to its virtual depth. If the accommodative response to a display point does not correspond to the virtual depth of that point, as determined by the binocular depth cues of convergence and stereopsis, the human visual system may experience an accommodation conflict, resulting in unstable imaging, harmful eye strain, headaches, and, in the absence of accommodation information, almost a complete lack of surface depth.
Therefore, there is a need for improved technologies to implement 3D displays that resolve these and other problems of the conventional approaches. The systems and techniques described herein are configured to work with the visual configuration of the typical human to address these challenges.